freebsd-dev/lib/libkvm/kvm_minidump_amd64.c
2014-02-12 15:57:38 +00:00

337 lines
8.6 KiB
C

/*-
* Copyright (c) 2006 Peter Wemm
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* AMD64 machine dependent routines for kvm and minidumps.
*/
#include <sys/param.h>
#include <sys/user.h>
#include <sys/proc.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include <sys/fnv_hash.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <nlist.h>
#include <kvm.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <machine/elf.h>
#include <machine/cpufunc.h>
#include <machine/minidump.h>
#include <limits.h>
#include "kvm_private.h"
struct hpte {
struct hpte *next;
vm_paddr_t pa;
int64_t off;
};
#define HPT_SIZE 1024
/* minidump must be the first item! */
struct vmstate {
int minidump; /* 1 = minidump mode */
struct minidumphdr hdr;
void *hpt_head[HPT_SIZE];
uint64_t *bitmap;
uint64_t *page_map;
};
static void
hpt_insert(kvm_t *kd, vm_paddr_t pa, int64_t off)
{
struct hpte *hpte;
uint32_t fnv = FNV1_32_INIT;
fnv = fnv_32_buf(&pa, sizeof(pa), fnv);
fnv &= (HPT_SIZE - 1);
hpte = malloc(sizeof(*hpte));
hpte->pa = pa;
hpte->off = off;
hpte->next = kd->vmst->hpt_head[fnv];
kd->vmst->hpt_head[fnv] = hpte;
}
static int64_t
hpt_find(kvm_t *kd, vm_paddr_t pa)
{
struct hpte *hpte;
uint32_t fnv = FNV1_32_INIT;
fnv = fnv_32_buf(&pa, sizeof(pa), fnv);
fnv &= (HPT_SIZE - 1);
for (hpte = kd->vmst->hpt_head[fnv]; hpte != NULL; hpte = hpte->next) {
if (pa == hpte->pa)
return (hpte->off);
}
return (-1);
}
static int
inithash(kvm_t *kd, uint64_t *base, int len, off_t off)
{
uint64_t idx;
uint64_t bit, bits;
vm_paddr_t pa;
for (idx = 0; idx < len / sizeof(*base); idx++) {
bits = base[idx];
while (bits) {
bit = bsfq(bits);
bits &= ~(1ul << bit);
pa = (idx * sizeof(*base) * NBBY + bit) * PAGE_SIZE;
hpt_insert(kd, pa, off);
off += PAGE_SIZE;
}
}
return (off);
}
void
_kvm_minidump_freevtop(kvm_t *kd)
{
struct vmstate *vm = kd->vmst;
if (vm->bitmap)
free(vm->bitmap);
if (vm->page_map)
free(vm->page_map);
free(vm);
kd->vmst = NULL;
}
int
_kvm_minidump_initvtop(kvm_t *kd)
{
struct vmstate *vmst;
off_t off;
vmst = _kvm_malloc(kd, sizeof(*vmst));
if (vmst == 0) {
_kvm_err(kd, kd->program, "cannot allocate vm");
return (-1);
}
kd->vmst = vmst;
vmst->minidump = 1;
if (pread(kd->pmfd, &vmst->hdr, sizeof(vmst->hdr), 0) !=
sizeof(vmst->hdr)) {
_kvm_err(kd, kd->program, "cannot read dump header");
return (-1);
}
if (strncmp(MINIDUMP_MAGIC, vmst->hdr.magic, sizeof(vmst->hdr.magic)) != 0) {
_kvm_err(kd, kd->program, "not a minidump for this platform");
return (-1);
}
/*
* NB: amd64 minidump header is binary compatible between version 1
* and version 2; this may not be the case for the future versions.
*/
if (vmst->hdr.version != MINIDUMP_VERSION && vmst->hdr.version != 1) {
_kvm_err(kd, kd->program, "wrong minidump version. expected %d got %d",
MINIDUMP_VERSION, vmst->hdr.version);
return (-1);
}
/* Skip header and msgbuf */
off = PAGE_SIZE + round_page(vmst->hdr.msgbufsize);
vmst->bitmap = _kvm_malloc(kd, vmst->hdr.bitmapsize);
if (vmst->bitmap == NULL) {
_kvm_err(kd, kd->program, "cannot allocate %d bytes for bitmap", vmst->hdr.bitmapsize);
return (-1);
}
if (pread(kd->pmfd, vmst->bitmap, vmst->hdr.bitmapsize, off) !=
vmst->hdr.bitmapsize) {
_kvm_err(kd, kd->program, "cannot read %d bytes for page bitmap", vmst->hdr.bitmapsize);
return (-1);
}
off += round_page(vmst->hdr.bitmapsize);
vmst->page_map = _kvm_malloc(kd, vmst->hdr.pmapsize);
if (vmst->page_map == NULL) {
_kvm_err(kd, kd->program, "cannot allocate %d bytes for page_map", vmst->hdr.pmapsize);
return (-1);
}
if (pread(kd->pmfd, vmst->page_map, vmst->hdr.pmapsize, off) !=
vmst->hdr.pmapsize) {
_kvm_err(kd, kd->program, "cannot read %d bytes for page_map", vmst->hdr.pmapsize);
return (-1);
}
off += vmst->hdr.pmapsize;
/* build physical address hash table for sparse pages */
inithash(kd, vmst->bitmap, vmst->hdr.bitmapsize, off);
return (0);
}
static int
_kvm_minidump_vatop_v1(kvm_t *kd, u_long va, off_t *pa)
{
struct vmstate *vm;
u_long offset;
pt_entry_t pte;
u_long pteindex;
u_long a;
off_t ofs;
vm = kd->vmst;
offset = va & (PAGE_SIZE - 1);
if (va >= vm->hdr.kernbase) {
pteindex = (va - vm->hdr.kernbase) >> PAGE_SHIFT;
if (pteindex >= vm->hdr.pmapsize / sizeof(*vm->page_map))
goto invalid;
pte = vm->page_map[pteindex];
if (((u_long)pte & PG_V) == 0) {
_kvm_err(kd, kd->program, "_kvm_vatop: pte not valid");
goto invalid;
}
a = pte & PG_FRAME;
ofs = hpt_find(kd, a);
if (ofs == -1) {
_kvm_err(kd, kd->program, "_kvm_vatop: physical address 0x%lx not in minidump", a);
goto invalid;
}
*pa = ofs + offset;
return (PAGE_SIZE - offset);
} else if (va >= vm->hdr.dmapbase && va < vm->hdr.dmapend) {
a = (va - vm->hdr.dmapbase) & ~PAGE_MASK;
ofs = hpt_find(kd, a);
if (ofs == -1) {
_kvm_err(kd, kd->program, "_kvm_vatop: direct map address 0x%lx not in minidump", va);
goto invalid;
}
*pa = ofs + offset;
return (PAGE_SIZE - offset);
} else {
_kvm_err(kd, kd->program, "_kvm_vatop: virtual address 0x%lx not minidumped", va);
goto invalid;
}
invalid:
_kvm_err(kd, 0, "invalid address (0x%lx)", va);
return (0);
}
static int
_kvm_minidump_vatop(kvm_t *kd, u_long va, off_t *pa)
{
pt_entry_t pt[NPTEPG];
struct vmstate *vm;
u_long offset;
pd_entry_t pde;
pd_entry_t pte;
u_long pteindex;
u_long pdeindex;
u_long a;
off_t ofs;
vm = kd->vmst;
offset = va & PAGE_MASK;
if (va >= vm->hdr.kernbase) {
pdeindex = (va - vm->hdr.kernbase) >> PDRSHIFT;
if (pdeindex >= vm->hdr.pmapsize / sizeof(*vm->page_map))
goto invalid;
pde = vm->page_map[pdeindex];
if (((u_long)pde & PG_V) == 0) {
_kvm_err(kd, kd->program, "_kvm_vatop: pde not valid");
goto invalid;
}
if ((pde & PG_PS) == 0) {
a = pde & PG_FRAME;
ofs = hpt_find(kd, a);
if (ofs == -1) {
_kvm_err(kd, kd->program, "_kvm_vatop: pt physical address 0x%lx not in minidump", a);
goto invalid;
}
if (pread(kd->pmfd, &pt, PAGE_SIZE, ofs) != PAGE_SIZE) {
_kvm_err(kd, kd->program, "cannot read %d bytes for pt", PAGE_SIZE);
return (-1);
}
pteindex = (va >> PAGE_SHIFT) & ((1ul << NPTEPGSHIFT) - 1);
pte = pt[pteindex];
if (((u_long)pte & PG_V) == 0) {
_kvm_err(kd, kd->program, "_kvm_vatop: pte not valid");
goto invalid;
}
a = pte & PG_FRAME;
} else {
a = pde & PG_PS_FRAME;
a += (va & PDRMASK) ^ offset;
}
ofs = hpt_find(kd, a);
if (ofs == -1) {
_kvm_err(kd, kd->program, "_kvm_vatop: physical address 0x%lx not in minidump", a);
goto invalid;
}
*pa = ofs + offset;
return (PAGE_SIZE - offset);
} else if (va >= vm->hdr.dmapbase && va < vm->hdr.dmapend) {
a = (va - vm->hdr.dmapbase) & ~PAGE_MASK;
ofs = hpt_find(kd, a);
if (ofs == -1) {
_kvm_err(kd, kd->program, "_kvm_vatop: direct map address 0x%lx not in minidump", va);
goto invalid;
}
*pa = ofs + offset;
return (PAGE_SIZE - offset);
} else {
_kvm_err(kd, kd->program, "_kvm_vatop: virtual address 0x%lx not minidumped", va);
goto invalid;
}
invalid:
_kvm_err(kd, 0, "invalid address (0x%lx)", va);
return (0);
}
int
_kvm_minidump_kvatop(kvm_t *kd, u_long va, off_t *pa)
{
if (ISALIVE(kd)) {
_kvm_err(kd, 0, "kvm_kvatop called in live kernel!");
return (0);
}
if (((struct vmstate *)kd->vmst)->hdr.version == 1)
return (_kvm_minidump_vatop_v1(kd, va, pa));
else
return (_kvm_minidump_vatop(kd, va, pa));
}